I mentioned before that sometimes (irregularly) *.jpg images that are
part of modules do not display correctly. Here is a screenshot of this
happening to me today:
http://karl.kleinpaste.org/.../WinSword-black-jpg.png
That module's images are now all *.jpg. As you can see, it's not even
consistently failing within a single page of the module, as there is one
successfully-displayed image and one failed black one.